1. Field of the Invention
The present invention relates to image forming apparatuses, and particularly, to an image forming apparatus that uses a cartridge equipped with a memory.
2. Description of the Related Art
A known electrophotographic image forming apparatus, which is a kind of an image forming apparatus, uses a process cartridge formed by combining an electrophotographic photosensitive drum and process units into a single cartridge unit. With this process-cartridge method, maintenance of the electrophotographic image forming apparatus can be performed by the user instead of a serviceman. This significantly improves the ease of use. Thus, this process-cartridge method has been widely used in electrophotographic image forming apparatuses.
A known process cartridge (referred to as “cartridge” hereinafter) is equipped with a memory (such as an integrated-circuit (IC) memory) that stores information to be transmitted to the main apparatus body of the electrophotographic image forming apparatus. When the cartridge is inserted in the main apparatus body, information can be exchanged between the main apparatus body and the cartridge. Thus, a controller of the main apparatus body can be notified of the status, such as the usage condition, of the cartridge (see U.S. Pat. No. 5,937,239).
Information, such as the lot number of the cartridge, the characteristics of the image forming apparatus, and the characteristics of the process units, is registered in the memory equipped in the cartridge. This facilitates maintenance of the main apparatus body or the cartridge. Moreover, image forming operation is controlled in accordance with the information stored in the memory so that the image forming operation can be performed under better conditions.
A contact-type electric connection technique is a known technique for electrically connecting the memory equipped in the cartridge of the image forming apparatus to the main apparatus body. In this technique, the memory and the main apparatus body are electrically connected to each other by using a connector or a contact formed of a spring, which have simple configurations and are advantageous in terms of cost (see US Patent Laid-Open No. 2003-0123896).
However, when strong impact force is applied to a positioning boss of the connector due to strong impact force or vibration applied to the main apparatus body during physical distribution, such as during transport, there is a possibility that the boss may break. Even if the connector were to be given a predetermined movable range for compensating for positional variations between the connector and the cartridge, the moving distance of the cartridge, which has a large mass, may exceed that movable range due to the strong impact. In this case, for example, the positioning boss of the connector, which serves as a positioning section for the connector and the cartridge, receives extremely large impact force. As a result, compact engagement sections, such as the positioning boss, may break or deform, possibly causing the connection state between an electric contact of the cartridge and an electric contact of the main apparatus body to deteriorate. On the other hand, expanding the movable range of the connector or increasing the strength of the positioning member would lead to an increase in size of the apparatus electric-contact mechanism.